Ok, So somewhere you may either want to know how much is this never ending project going to cost, or you just want to hear my input on the topic. Either way, I can't imagine actually itemizing what I have spent, so I will just place here some of the things to consider. It is no secret that this hobby costs a lot of cash, in fact as much as your willing and able to part with.
The shoebox I store my receipts in will need a hydraulic press just to close it soon. What I would say is that to lessen the blow to your cashflow consider some of the following.
Having a really really good idea as to the type of life you want to keep and what you want your tank to look like then not changing your mind half way. Should be able to subtract at least 10% from the normal costs. That doesn't mean that you need to itemize all you want before you start. Just have a plan in hand.
Choosing appropriate equipment for your tanks desired outcome the first time around should be worth another 10% or more.
Finding a good, or several good mentors will save some cash and learning pain. Finding a bad one could cost you double.
Having adequate emergency backup plans in place and hardware on hand should shave a few more % points off the total cost.
Going with DIY for as much as you can should shave another 10% for even a novice handyman. Course if you can't change a lightbulb and still try DIY you could loose much more than 10%.
Deduct triple the cost you spend on any Currently respected books that you actually read, as reading them should save you at least that much. Deduct the cost of the book for any additional re-reads of the same book. Referencing same books doesn't count for a deduction, but is good also.
Never shopping in an LFS without a Specific Shopping list and a pair of Blinders. Subtract at least $25 for every time you make it out of the store without something "Extra" in tow.
Subtract much heartache and cash if you follow regular tank maintenance procedures... add the cost of a crash or three if you do not.
Subtract another $25 for every 24hrs you spend reading forums and aquarium related websites on the net... $30 if your also able to separate the wheat from the chaff... $40 if you can also not jump on the latest bandwagon if your tank is running fine as it is.
Subtract 5% if your significant other thinks spending on the tank is crazy ... add 5% if they are a an impulse buyer, you do not have any such controls, or you hide the expenditures.
Subtract 5% every time you find at least 3 worthy independent opinions that agree on what you need before you buy it.
Subtract 5% if you can actually both fully understand and never deviate from the instructions on any and all additives you are going to use.
Subtract 7% if you are going to use good quarantine methods for all additions to your tank... add 10% if you don't.
Subtract 3% for every week that you spend at least 1 hour actually looking at your tank every day... add 5% if you don't do it more than once a week.
Subtract 3% if you have the capacity and equipment ready to do a large water change within 1 hour of the need for one. Add 3% if you do not.
Subtract 5% if you know at least the basic needs and wants of anything you add to your tank... add 10% if you couldn't care less as long as it looks good.
Add 5% if you haven't been out on the town in over a month and can't stop dreaming about adding things to your tank.
Add 5% if you do not have a LFS within 15 minutes of your location that stocks all the basics.
Add 5% if your a test tube junky... add 7% if you will also be using crap tests.
Add 20% if your the impatient type personality... toss in an extra 5% if your significant other is also.
Double your cost if your planning on using minimally treated tap water... scratch that (hehe), Do not use tap water unless your sure it is pristine.
Toss on another 10% for each piece of automation your planning. Throw in the cost of your time if your not planning any type of automation.
Add double the total cost if you are unable to identify and learn from your mistakes... subtract double if you can and are also able to learn from the mistakes of others.
I could likely continue this for quite some time.... This was fun! I hope that those %'s don't add up to over 100%. I was just guessing the %'s based on my feelings of importance for the specific item I don't mean them to be set in stone. I hope any of this helps.